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El-Idreesy, T. T., and E. L. Clennan, "Hydrolytic stability of N-Methyl-2,6-dimesitylpyrylogen bis-tetrafluoroborate", Journal of Organic Chemistry, 2011. Abstract
El-Idreesy, T. T., and E. L. Clennan, "Hydrolytic stability of N-Methyl-2,6-dimesitylpyrylogen bis-tetrafluoroborate", Journal of Organic Chemistry, 2011. Abstract

The synthesis and characterization of a new mesityl ring substituted pyrylogen with a substantially decreased rate of reaction with water is reported. Computational and experimental data are presented that suggest that addition of water to the pyrylium ring of this highly sterically shielded pyrylogen is reversible. On the other hand, experimental data suggest that the overall hydrolysis of this new sterically

Alaasara, M., C. Tschierskeb, and M. Prehmb, "Hydrogen-bonded Supramolecular Complexes Formed Between Isophthalic Acid and Pyridine-Based Derivatives", Liquid Crystals, 2011. Abstract

Two types of supramolecular liquid crystals were prepared through the formation of double hydrogen-bonded complexes between isophthalic acid (A) and two different groups of pyridine-based derivatives ( In and Ia-e). The first group of the base, In (molecular formula 4-CnH2n+1OC6H4COOC6H4-N=N-C5H4N) homologues differ from each other by the number of carbon atoms (n) in the alkoxy chain, which varies between 8, 10, 12 and 14 carbons. The second group of the pyridine-based derivatives, Ia-e (molecular formula 4-X-C6H4COOC6H4-N=N-C5H4N) analogues differ from each other by the terminal polar substituent, X, that changes between OCH3, CH3, H, NO2 and Br groups. In this manner two different groups of complexes are formed, one of them is A : 2In, (Group A), and the other is A : 2Ia-e, (Group B). All complexes were investigated for their mesophase behaviour by differential scanning calorimetry and polarised light microscopy. The formation of 1:2 hydrogen-bonded complexes was confirmed by FTIR spectroscopy and binary phase diagrams. Most complexes A and B show nematic and/or SmA phases. X-ray diffraction of the SmA phase of a representative complex of type A indicates a layer distance corresponding to only half of the length of the H-bonded complexes which is interpreted by a phase structure where these complexes adopt a U-shape which intercalate and form non-polar SmA phases.

Farghaly, T. A., S. M. Gomha, E. M. H. Abbas, and M. M. Abdalla, "Hydrazonoyl Halides As Precursors For New Fused Heterocycles of5?- Reductase Inhibitors", Arch. Pharm. Chem. Life Sci., 2011.
Zeid, K. A. M., M. B. Mohamed, and S. M. El-Shall, "Hybrid Au-CdSe and Ag-CdSe Nanoflowers and Core-Shell Nanocrystals via One-Pot Heterogeneous Nucleation and Growth", Small, 2011. Abstract

A general approach, based on heterogeneous nucleation and growth of CdSe nanostructures on Au or Ag nanocrystals, for the synthesis of AuCdSe and AgCdSe hybrid nanostructures is developed. The new approach provides a versatile one-pot route for the synthesis of hybrid nanoflowers consisting of a gold or silver core and multipod CdSe rods or an intact CdSe shell with controlled thickness, depending on the nucleation and growth parameters. At lower growth temperatures such as 150 degrees C, the CdSe clusters are adsorbed on the surface of the metal cores in their surface defects, then multiple arms and branches form, resulting in nanoflower-shaped hybrid structures. Increasing the size of the metal core through the choice of the reducing and capping agents results in an improvement of the interface between the metal and CdSe domains, producing coreshell structures. The growth temperature appears to be the most important factor determining the nature of the interface between the metal and CdSe domains. At relatively high temperatures such as 300 degrees C, the formation of large, faceted Au cores creates preferential growth sites for the CdSe nanocrystalline shell, thus resulting in well-defined AuCdSe coreshell structures with large interfaces between the Au and CdSe domains. The present approach is expected to foster systematic studies of the electronic structures and optical properties of the metal semiconductor hybrid materials for potential applications in photovoltaic and nanoelectronic devices.

Mokbel, A. N., O. E. S. Tookhy, A. A. Shamaa, L. A. Rashed, D. Sabry, and A. E. M. Sayed, "Homing and Reparative Effect of Intra-Articular Injection of Autologus Mesenchymal Stem Cells in Osteoarthritic Animal Model", BMC Musculoskeletal Disorders, 2011. Abstract

This work aimed to study the homing evidence and the reparative effect of mesenchymal stem cells (MSCs) in the healing process of induced osteoarthritis in experimental animal model (donkeys). Twenty-seven donkeys were equally divided into 3 groups based on the observation period after induction of arthritis (3, 6 and 9 weeks) to achieve different degrees of osteoarthritis. Each group was subdivided into three subgroups of three animals each based on the follow-up period (1, 2 and 6 months) after treatment. The induction was done through intra-articular (IA) injection of 2ml of Amphotericin-B in both carpal joints. MSCs were harvested in a separate procedure, labeled with green fluorescent protein (GFP) using monster GFP vector and suspended in hyaluronic acid for IA injection. Treatment approaches consisted of cell-treatment using MSCs suspended in 3 ml of hyaluronic acid (HA) for the right carpal joint; and using the same amount of (HA) but without MSCs for the left contralateral carpal joint to serve as a control. Animals were assessed clinically and radiologically before and after treatment. Synovial fluid was also evaluated. Histopathologically; articular cartilage structural changes, reduction of articular cartilage matrix staining, osteophyte formation, and subchondral bone plate thickening were graded. Data was summarized using median and percentile for scores of histopathologic grading. Comparison between groups was done using non-parametric Mann Whitney test. The reparative effect of MSCs was significant both clinically and radiologically in all treated groups (P < 0.05) compared to the control groups. Fluorescence microscopy of sections of the cell-treated joints of all animals indicated that the GFP-transduced injected cells have participated effectively in the reparative process of the damaged articular surface and have integrated within the existing articular cartilage. The cells were associated with the surface of the cartilage and, were also detected in the interior. Homing was confirmed by the incorporation of injected GFP-labeled MSCs within the repaired newly formed cartilage. Significant recovery proves that the use of IA injection of autologous MSCs is a viable and a practical option for treating different degrees of osteoarthritis.

Mokbel, A. N., O. E. S. Tookhy, A. A. Shamaa, D. Sabry, L. A. Rashed, and A. E. M. Sayed, "Homing and Efficacy of Intra-articular Injection of Autologous Mesenchymal Stem Cells in Experimental Chondral Defects in Dogs", Clinical and Experimental Rheumatology, 2011. Abstract

This study was intended to verify the likelihood of homing of intra-articularily (I.A.) injected mesenchymal stem cells (MSCs) and its involvement in the healing process of experimentally induced, acute and chronic, partial chondral defects in dogs.

Gadallah, A. - S., and R. Michalzik, "High-Output-Power Single-Higher-Order Transverse mode VCSEL With Shallow Surface Relief", Ieee Photonics Technology Letters, vol. 23, issue 15, 2011. AbstractCU-PDF.pdf

We report high-power single-higher-order transverse mode emission of a large-area oxide-confined rectangular-shaped vertical-cavity surface-emitting laser (VCSEL) with a multispot shallow surface relief. Both a record-high output power of 12 mW and a record-low differential series resistance of 18 ohms are achieved. Stable single-higher-order transverse mode emission with a sidemode suppression ratio (SMSR) exceeding 35 dB is maintained up to thermal rollover. Single-polarization lasing along the major axis is achieved with 27.5-dB spectral orthogonal polarization suppression ratio at thermal rollover. Measurements of near- and far-field intensity profiles of the higher-order mode are also presented.

Abdelaziz, W. S., "High gain predictions for Ni-like Gd ion", Optics Communications, vol. 284, issue 12, pp. 2859-2862, 2011. AbstractCU-PDF.pdf

Atomic structure data and effective collision strengths for 1s22s22p63s23p6 3d10and 54 ?ne-structure levels contained in the con?gurations 1s22s22p63s23p63d9 4l (l=s, p, d, f) for the nickel-like Gd ion. These data are used in the determination of the reduced population for the 55 ?ne structure levels over a wide range of electron densities (from 1021 to 1023) and at various electron plasma temperatures. The gain coef?cient for those transitions with positive population inversion factor are determined and plotted against the electron density.

Abdelrazek, F. M., A. A. Fadda, and S. S. Mohamed, "Heterosynthesis using nitriles: Novel pyrrolo[2,3-b]pyridines", Internat. J. Org. Chem., 2011. Abstract

2-Amino-4-benzoyl-1-arylpyrrole-3-carbonitriles react with arylidene malonodinitriles, ?-ketoesters and ?-diketones to afford pyrrolo[2,3-b]pyridine derivatives.

Saleh, H. M., A. S. Shaker, A. M. Saafan, and A. K. H. Ibrahim, "Herpes Virus Reactivation by Low-Intensity Diode and Co2 Lasers", Photomedicine and Laser Surgery, 2011. Abstract

Background:The herpes virus enters into latency after symptomatic or asymptomatic herpetic infection. During latency, the virus has no impact on infected cells. However, internal or external stimuli, including certain lasers, can induce virus reactivation.

Ramadan, A., M. M. Hashem, K. Abo-EL-Sooud, and A. Azooz, "Herbal remedies of Nanobacteria", Nano Science and Nano Tecknology, 2011. Abstract

Ethnobotanical surveys were carried out to document herbal remedies used in the management of nanobacterial opportunistic infections. The kidney is the main part of the urinary tract. Drinking too much or too little water, administration of antibiotics as well as excess consumption of calcium or oxalic acid causes awakening of the kidneys resulting in renal disorders. When the kidneys are not filtering the blood properly, toxins accumulate causing lower sciatic pain, kidney stones, bladder stones, painful or difficult urination, and urinary tract infection. These types of disorders in the renal system can be treated with Ayurveda, an indigenous system of medicine in India. In Ayurveda, single plant or combinations of different plants are used in the treatment (Rajurkar and Damame 1998). Nanobacteria appear as self-propagating calcifying macromolecular complexes found in bovine and human blood and blood products. Nanobacteria were found to be present in fetal bovine serum and cultured cell lines, to arouse immune response and to infect humans, and were published as an infectious cause for pathological calcification (Kajander and Ciftcioglu 1998). These are very small, Gram negative bacteria. They belong to the Proteobacteria group and are about 1/20 the size of most of their larger cousins in this group. They may play a pathogenic role in kidney stones and atherosclerosis. These bacteria are unique by developing a needle-shaped calcium apatite cell wall, forming an enclosure around the organism. This review of literature elucidates previous and current status of herbal remedies in treating nanobacteria.

Aboul-Soud, M. A. M., A. M. Al-Othman, G. E. El-Desoky, Z. A. Al-Othman, K. Yusuf, J. Ahmad, and A. A. Al-Khedhairy, "Hepatoprotective Effects of Vitamin E/Selenium Against Malathion-Induced Injuries on the Antioxidant Status Andapoptosis-Related Gene Expression in Rats", Journal of Toxicological Sciences, 2011. Abstract

The present study is undertaken to evaluate the protective effect of vitamin E(?-tocopherol) and selenium (Se) against malathion (MTN)-induced oxidative stress and hepatic injuriesin experimental rats. Male rats were randomly divided into eight groups comprised of 10 rats each. The1st group served as a negative control (CN), whereas the 2nd was supplemented with a combination of?-tocopherol (100 mg kg-1 body weight, b.w.)/Se (0.1 mg kg-1 bw). The 3rd, 4th and 5th groups were respectivelyadministered with increasing doses of MTN equivalent to 1/50 LD50 (M1/50), 1/25 LD50 (M1/25) and 1/10LD50 (M1/10), respectively. The 6th, 7th and 8th groups were administered the same doses of MTN as in the3rd, 4th and 5th groups with a concomitant supplementation with ?-tocopherol/Se. Subchronic exposure ofrats to MTN for 45 days resulted in statistical dose-dependent decrease in acetylcholinestrase (AChE)activity, increase in oxidative stress marker lipid peroxidation (LPO) and reduction in reduced glutathione(GSH) level. Moreover, the levels of glutathione persoxidase (GPx), superoxide dismutase (SOD) andcatalase (CAT) were significantly decline in response to MTN exposure in a dose-dependent fashion. Furthermore,histopathological studies of liver in the rats which received MTN exhibited, moderate to severedegenerative and necrotic changes in the hepatocytes. Notably, the administration of ?-tocopherol/Se protectedthe liver of rats exposed to MTN as evidenced by the appearance of normal histological structures,significant attenuation of the decline in all antioxidant enzymes tested (i.e. GPx, SOD and CAT), significantrecovery in the GSH level and statistical reduction in LPO, as compared to the experimental rat.

Sayed, M. M. A. A., and A. M. Soliman, "Hepatoprotective and Antioxidant Effects of Cichorium Endivia L", Journal of Medicine and Medical Sciences, 2011. Abstract

The current study was carried out to elucidate the effect of hydroalcoholic extract of Cichorium endivia L.leaves (HCE) against acetaminophen-induced oxidative stress and hepatotoxicity in male rats. Oral administration of acetaminophen produced liver damage in rats as manifested by the significant increase in liver MDA and serum total lipids, total cholesterol, creatinine, total bilirubin and enzyme activities (AST, ALT and ALP). While a significant decrease in the levels of liver GSH, GST, SOD, CAT, serum total protein and albumin was recorded. Pre-treatment of rats with C.endivia leaves extract or silymarin for 21 days succeeded to modulate these observed abnormalities resulting from acetaminophen as indicated by the pronounced improvement of the investigated biochemical and antioxidant parameters. These results substantiate the potential hepatoprotective and antioxidant activity of C.endivia leaves extract. In addition, the hepatoprotective activity of HCE was found to be compatible with silymarin as a known hepatoprotective drug.

Samer, M., C. Loebsin, M. Fiedler, C. Ammon, W. Berg, P. Sanftleben, and R. Brunsch, "Heat Balance and Tracer Gas Technique for Airflow Rates Measurement and Gaseous Emissions Quantification in Naturally Ventilated Livestock Buildings", Energy and Buildings, 2011. Abstract

Experiments were performed to study the airflow rates (AFRs) in a naturally ventilated building through four summer seasons and three winter seasons. The AFRs were determined using heat balance (HB), tracer gas technique (TGT) and CO2-balance as averages of the values of all experiments carried out through the different seasons. The statistical analyses were correlation analysis, regression model and t-test. Continuous measurements of gaseous concentrations (NH3, CH4, CO2 and N2O) and temperatures inside and outside the building were performed. The HB showed slightly acceptable results through summer seasons and unsatisfactory results through winter seasons. The CO2-balance showed unexpected high differences to the other methods in some cases. The TGT showed reliable results compared to HB and CO2-balance. The AFRs, subject to TGT, were 0.12 m3 s?1 m?2, 1.15 m3 s?1 cow?1, 0.88 m3 s?1 LU?1, 56 h?1, 395 m3 s?1 and 470 kg s?1 through summer seasons, and 0.08 m3 s?1 m?2, 0.83 m3 s?1 cow?1, 0.64 m3 s?1 LU?1 39 h?1, 275 m3 s?1 and 328 kg s?1 through winter seasons. The AFRs are not independent values, rather they were estimated for specific reference values, which are: area, cow and LU as well as rates. The emission rates through summer seasons, subject to TGT, were 9.4, 40, 3538 and 2.3 g h?1 cow?1; and through winter seasons were 4.8, 19, 2332 and 2.6 g h?1 cow?1, for NH3, CH4, CO2 and N2O, respectively.

El-Kolaly, H. A., and S. M. Seif, "Hadronic Production of MSSM Higgs Boson with a Pair of Stops at LHC", Physical Review D, 2011. Abstract

We present the SUSY QCD corrections to the production of light neutral MSSM Higgs boson with a pair of supersymmetric scalar partners of the top quark at next-to-leading order at LHC. We study the dependence of the lowest order total cross section on both the renormalization/factorization scale and the Higgs mass in the framework of minimal supergravity, taking the point SPS1a as a benchmark, for the numerical calculations. The dependence of the total cross section is strong. Including the NLO SUSY QCD corrections significantly reduce and stabilize the dependence of the lowest order total cross section on the renormalization/factorization scale.

El-Ghani, M. A. M., M. M. Abou-EL-Enain, A. I. Aboel-Atta, and E. A. Hussein, "Habitat Heterogeneity and Soil-vegetation Relations in South of the Nile Delta, Egypt", Ecologia Mediterranea, 2011. Abstract

Floristic composition and soil characters in representative habitats of the southern Nile Deltaregion in Qalyubia were analyzed in terms of habitat variations and species diversity. A totalof 90 sites were surveyed and nineteen environmental factors were recognized in four main habitats: canal banks, cultivated lands, waste lands and sandy plains. Basic statistical treatments were established by using SPSS v. 10.0. The produced data were subjected to cluster analysis by using MVSP v. 3.1; indirect and direct ordination methods i.e. Detrended and Canonical Correspondence analyses, respectively by using CANOCO v. 4.5. A total of 164 species representing c. 7.7% of the Egyptian plant species were recorded and their life-form spectrum was identified. The majority of species were belonging to the families: Gramineae, Compositae, Leguminosae and Cruciferae.